Role of nitric oxide in the promoting effect of HIV type 1 infection and of gp120 envelope glycoprotein on interleukin 4-induced IgE production by normal human mononuclear cells

Effect of deworming on Th2 immune response during HIV-helminths co-infection

Background

Helminths infections have been suggested to worsen the outcome of HIV infection by polarizing the immune response towards Th2. The purpose of this study is to determine the activity of Th2 immune response by measuring total serum IgE level during symptomatic and asymptomatic HIV infection with and without helminths co-infection and to define the role of deworming and/or ART on kinetics of serum IgE.

Methods

This prospective comparative study was conducted among symptomatic HIV-1 infected adults, treatment naïve asymptomatic HIV positive individuals and HIV negative apparently healthy controls with and without helminths co-infection. Detection and quantification of helminths and determination of serum IgE level, CD4⁺, and CD8⁺ T cell count were done at baseline and 12 weeks after ART and/or deworming.

Results

HIV patients co-infected with helminths showed a high level of serum IgE compared to HIV patients without helminths co-infection (1,688 [IQR 721–2,473] versus 1,221 [IQR 618–2,289] IU/ml; P = 0.022). This difference was also markedly observed between symptomatic HIV infected patients after with and without helminths infection (1,690 [IQR 1,116–2,491] versus 1,252 [703–2,251] IU/ml; P = 0.047). A significant decline in serum IgE level was observed 12 weeks after deworming and ART of symptomatic HIV infected patients with (1,487 versus 992, P = 0.002) and without (1,233 versus 976 IU/ml, P = 0.093) helminths co-infection. However, there was no significant decrease in serum IgE level among asymptomatic HIV infected individuals (1,183 versus 1,097 IU/ml, P = 0.13) and apparently health controls (666 IU/ml versus 571, P = 0.09) without helminths co-infection 12 weeks after deworming.

Conclusions

The significant decline of serum IgE level 12 weeks after deworming of both symptomatic and asymptomatic patients indicate a tendency to down-regulate the Th2 immune response and is additional supportive evidence that deworming positively impacts HIV/AIDS diseases progression. Thus, deworming should be integrated with ART program in helminths endemic areas of tropical countries.

HIV and asthma, is there an association?

OBJECTIVE

To evaluate whether asthma and airway hyper-responsiveness are associated with HIV infection.

METHODS

We reviewed the literature on HIV-associated pulmonary diseases, pulmonary symptoms, and immune changes which may play a role in asthma. The information was analyzed comparing the pre-HAART era to the post-HAART era data.

RESULTS

HIV-seropositive individuals commonly experience respiratory complaints yet it is unclear if the frequency of these complaints have changed with the initiation of HAART. Changes in pulmonary function testing and serum IgE are seen with HIV infection even in the post-HAART era. An increased prevalence of asthma among HIV-seropositive children treated with HAART has been reported.

CONCLUSION

The spectrum of HIV-associated pulmonary disease has changed with the introduction of HAART. Current data is limited to determine if asthma and airway hyper-responsiveness are more common among HIV-seropositive individuals treated with HAART.

Serum IgE levels of tuberculosis patients in a tropical setup with high prevalence of HIV and intestinal parasitoses

Tuberculosis remains a major health problem worldwide in the era of HIV/AIDS. Co-infection with intestinal parasites has been suggested to worsen the outcome of infection by polarizing the immune response towards Th2. This study investigated serum IgE levels of 241 tuberculosis patients and compared the IgE profiles in the tuberculosis patients either with or without intestinal helminthic infection and/or HIV infection. The serum levels of IgE in tuberculosis patients before initiation of antimycobacterial chemotherapy were found to be 1722 +/- 1290 IU/ml (Mean +/- SD) in HIV seronegatives and 2366 +/- 1849 IU/ml in HIV seropositives. Further, the IgE level was significantly higher in patients coinfected with intestinal helminthes and HIV compared to those infected with helminthes or without coinfection (P < 0.05). Anti-tuberculosis chemotherapy significantly reduced serum IgE levels in HIV seronegative tuberculosis patients (P < 0.05). These findings might indicate an active role of therapy in shifting the immune response towards Th1 which is crucial for prognosis in tuberculosis patients.

Wheat gliadin promotes the interleukin-4-induced IgE production by normal human peripheral mononuclear cells through a redox-dependent mechanism

Increased levels of serum IgE have been described in gliadin-intolerant patients; however, biological mechanisms implicated in this immunoglobulin production remained unknown. In this study, we demonstrated that in vitro crude gliadins and gliadin lysates (Glilys) promoted the IL-4-induced IgE production by human peripheral blood mononuclear cells (PBMC), indicating that the biological process related to gliadin intolerance and/or allergy may lead to IgE production in vivo. It was found that crude gliadin and Glilys potentiated, after 13 days of culture in a dose-dependent manner, IL-4-induced IgE production and, to a lesser extent, the IgG production, while they did not affect IgA or IgM productions. This promoting effect of gliadin and Glilys on the IL-4-induced activation of normal human PBMC was also observed on the early release (2 days) of the soluble fraction of CD23, suggesting its possible involvement in IgE potentiation. The promoting effect of crude gliadin and Glilys appeared to be indirect because they did not modify purified B-lymphocytes IgE production after IL-4 and anti-CD40 monoclonal antibody stimulation. In addition, as revealed by luminol-dependent chemiluminescence, we demonstrated that crude gliadin and Glilys promoted a substantial production of free radicals by normal human PBMC, treated or not with IL-4. This redox imbalance associated with an increased IgE production led us to evaluate the effect of pharmacological antioxidants (N-acetyl-cysteine (NAC) and Cu/Zn-superoxide dismutase (SOD1)) on IgE production by human PBMC. The NAC and the intracellularly delivered SOD1 were found to suppress the IL-4+/-crude gliadin or Glilys-induced IgE production by normal human PBMC. Taken together, these data indicated that gliadin specifically enhanced IL-4-induced IgE production by normal human PBMC, probably by the regulation of redox pathways, and that this 'pro-allergenic' effect could be counteracted by natural antioxidants: thiols and/or vectorized SOD1.

Serum immunoglobulin E levels in human immunodeficiency virus-infected children with pneumonia

Elevated serum immunoglobulin E (IgE) levels have been reported in association with human immunodeficiency virus (HIV) infection in adults, but there is little information in children. The aim of the present study was to compare serum IgE levels in HIV-positive and -negative children hospitalized with pneumonia in South Africa and to investigate whether IgE may be useful as a marker of specific infections or prognosis in HIV-infected children. History, examination, blood tests, and induced sputum or bronchoalveolar lavage were carried out. Of 122 children [45% female, median age 8 months (3-20 months)], 81 were infected with HIV. A history of allergy or asthma was present in three children (two of whom were HIV positive). Serum IgE was higher in HIV-infected children [83 (33-147) vs. 29 (6-113) IU/l; p = 0.011] as was immunoglobulin G (IgG) [49 (37-63) vs. 27.5 (23-34) g/l; p < 0.001]. CD4 lymphocytes [600 (330-1,210) vs. 1,900 (1,500-3,030) cells/ micro l], percentage CD4 cells [13.6 (9.4-20.3) vs. 40.1 (31.1-44.9)] and CD4 : CD8 ratio [0.3 (0.2-0.4) vs. 2 (1.4-2.8)] were lower in HIV-positive children (p < 0.001 for all). Bacteremia occurred in 12 (10%) children; other specific pathogens identified included Mycobacterium tuberculosis in eight (7%) and Pneumocystis carinii in nine (7%). There was no correlation with CD4 count, CD4 : CD8 ratio, or the presence of specific pathogens, and IgE level. In-hospital mortality (11%) did not correlate with IgE levels. HIV-infected children with pneumonia have higher serum IgE compared with seronegative patients. In HIV-positive children, IgE levels did not correlate with the degree of immunosuppression or with outcome.

Non-allergic rhinitis: diagnosis and management

Patients in the rhinitis clinic with negative skin prick tests present a challenge. Non-allergic rhinitis consists of a variety of conditions including infection, hormonal changes, drugs and autonomic dysfunction. There is also a range of systemic disorders to be considered. The pathogeneses of many of these are less well understood than that of allergic rhinitis, diagnosis and treatment pathways are also more complex. A detailed accurate history needs to be taken followed by relevant investigations which may include allergen challenge, because skin prick and RAST-negative allergic rhinitis is now recognised. Nitric oxide levels may prove helpful: elevated levels suggest inflammation, very low levels indicate the possibility of primary ciliary dyskinesia or cystic fibrosis. Treatment is of the underlying cause when found: for those without obvious pathology a trial of combined therapy with topical corticosteroids plus antihistamine or plus anti-cholinergic may be worth while. A complex inter-relationship between allergic and infectious rhinitis is becoming apparent.

Cerebral blood flow pulsatility deficits in HIV+ poly substance abusers: differences associated with antiviral medications

This study examines the influence of HIV-seropositivity and antiviral medications on cerebral blood flow in cocaine abusers. Forty-five HIV negative (HIV-) cocaine abusers, 36 HIV positive (HIV+) cocaine abusers (CD4; mean 378, +/-229) and 27 control HIV- subjects were studied. Blood flow velocity and pulsatility were determined for the anterior and middle cerebral arteries using transcranial Doppler sonography (TCD). Psychological assessments, which included the psychiatric symptom checklist (SCL-90R), hopelessness (Beck) and well-being (Ellison) questionnaires revealed greater psychiatric distress in HIV+ cocaine abusers than the other groups. HIV- cocaine abusers and HIV+ cocaine abusers not receiving antiviral medications (n=25 of 36) had elevated pulsatility values, indicating increased resistance in the cerebral blood vessels in comparison to control subjects. HIV+ cocaine abusers using antiviral medications (n=11 of 36) had pulsatility values similar to HIV- control subjects. Interestingly, there was no significant relationship between intensity of psychiatric distress reported by HIV+ cocaine abusers and perfusion deficits. Our findings suggest that unmedicated HIV+ cocaine abusers have cerebrovascular deficits, which are similar to HIV- cocaine abusers. In addition, the use of antiviral medications appears to be associated with a reduction of these deficits in HIV+ cocaine abusers. Nevertheless, more studies will be needed before any conclusion can be reached regarding possible beneficial effects of these agents on the cerebral vasculature.